The aim in imaging methods, in particular in digital recording methods and also used in medical imaging, for example in computed tomography, is to increase the resolution of generated images. This can be achieved, for example, by reducing the pixel surface of a detector in the case of an X-ray device by reducing the detection surface of an X-ray detector. It is known for this purpose to cover the pixel surface at least partially with a perforated metal sheet or, in the case of optical detectors, with a shadow mask.
JP 2004-283343-A discloses for example an X-ray computer tomograph in which a shadow mask is arranged between an X-ray source and an X-ray detector. The shadow mask has a multiplicity of holes such that the projection surface of an X-ray projection is smaller than the detector surface made available by the X-ray detector. As already mentioned, the resolution of an image determined with the aid of the X-ray computed tomograph is increased with the aid of. the shadow mask.
Since the shadow mask is generally not required for all the measurement operations in an imaging unit, this is used according to requirements. However, there proves to be a problem here in adjusting the shadow mask, if required, above the pixel matrix of the detector used.